It is difficult to know how long a minute really is. Why not make a game of guessing
a stop watch
Instruct everyone to find a space to themselves (preferably away from the ones who distract them!)
Everyone is to sit down and bow their heads
the leader says Go! and sets the stop watch off.
The goal is to guess how long a minute is.
Once a participant thinks they have guessed a minute then they raise their hand or lie down or stand up; make it obvious they have finished
the closest one to 60 seconds is the winner,
you can also have a discussion about how time appears to change depending on what you are doing.